SB20260320108 - Exposure of sensitive information to an unauthorized actor in Linux kernel ipv6

Description

This security bulletin contains information about 1 vulnerability.

1) Exposure of sensitive information to an unauthorized actor (CVE-ID: CVE-2026-23247)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to improper output neutralization in the TCP sequence number generation mechanism when handling SYN cookies. A remote attacker can send specially crafted TCP connection requests to disclose sensitive information.

The attacker can exploit the side-channel to infer TCP source ports, enabling off-path attacks that leak information about connection parameters.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/165573e41f2f66ef98940cf65f838b2cb575d9d1
• https://git.kernel.org/stable/c/46e5b0d7cf55821527adea471ffe52a5afbd9caf
• https://git.kernel.org/stable/c/eae2f14ab2efccdb7480fae7d42c4b0116ef8805